The present invention relates to an apparatus for purifying water and particularly to an apparatus for use with a purifying agent such as iodine.
Iodine rapidly, efficiently and safely kills bacteria, viruses, and cysts in water. Also, iodine has a number of chemical properties which make it superior to other purifying agents such as chlorine as a germ-killer and decontaminant. Iodine is weak chemically and reacts very slowly, if at all, with organic material. Chlorine, on the other hand, is chemically strong and reacts very quickly with the chemical compounds normally present in water. As a result, chlorine is used up at a high rate, rendering it inefficient as a germ-killer. The iodine residual is extremely stable, retaining its germicidal potency, while the chlorine residual is delicate and unstable. Also, chlorine combines rapidly with the nitrogenous matter present in water to form chloramines, which are basically ineffective as germ-killers. pH and sunlight have a relatively small effect on the germ-killing power of iodine. With chlorine, these factors have a pronounced effect. Finally, very little iodine can volatilize from water due to the low vapor pressure of the element. Accordingly, there is no odor or taste problem with iodinated water. By contrast, chlorinated water has an objectionably strong odor and taste.
Although the chemical properties of iodine are superior to chlorine as a water purifying agent, and the safety of iodine has been established by decades of extensive medical research, iodine has only recently begun to capture segments of the water purification market. One of the reasons for this has been the problem of cheaply and efficiently feeding iodine into a water supply. It is therefore an object of the present invention to provide an apparatus for feeding a water purifying agent such as iodine into a water supply system which can be cheaply manufactured, is simple to install and provides long-life and low maintenance operation.